This application claims the benefit of the Korean Application No. P2001-025899 filed on May 11, 2001, which is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a liquid crystal display panel, and more particularly, to a method for forming a spacer of a liquid crystal display panel. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for simplifying a process for forming a spacer with a constant thickness and shape.
2. Discussion of the Related Art
Conventionally, a glass bead or a plastic bead having a certain particle diameter is formed on two sheets of substrates to maintain a constant cell-gap. When such spacer particles are randomly scattered on the substrate, so that the spacer is located at the pixel region, a contrast of the liquid crystal display panel is degraded as the incident light is scattered.
In order to solve the problems, there has been proposed a method for forming a spacer by photolithography.
In this method, a photoresist film is coated on a substrate, to which ultraviolet rays are selectively irradiated through a mask and developed to form a spacer in a dot or stripe type, so that a spacer can be selectively formed at the desired location.
In addition, since a cell-gap between the two sheets is controlled by the thickness of the photoresist film, it is easily and precisely controlled.
A method for forming a spacer of a liquid crystal display panel of the conventional art will now be described with reference to FIGS. 1A to 1D.
As shown in FIG. 1A, a photoresist film 2 is coated on a substrate 1 by a spin-coating method.
In FIG. 1B, ultraviolet rays are selectively irradiated on the photoresist film 2 through a mask (not shown) and developed to form a pattern of the photoresist film 2.
A rubbing is performed on the substrate 1 on which the pattern of the photoresist film 2 is formed, as shown in FIG. 1C. Thus, a desired orientation is obtained when a liquid crystal is filled therein.
Thereafter, as shown in FIG. 1D, the other substrate 3 is attached on the substrate 1, so that the two sheets of substrates of the liquid crystal display panel have a constant cell-gap therebetween.
However, the method for forming a spacer of a liquid crystal display panel of the conventional art has the following problems.
Since the photoresist film is exposed through the photolithography method, the spacer area remaining after the development of the photoresist film is enlarged as the photoresist film is more distanced from the light source.
Thus, if the spacer forming region does not have an enough alignment margin, it could be formed to be located at the pixel region, thereby degrading a display characteristic.
In addition, in the case that the photoresist film is formed by the spin-coating method, the film thickness is increased as it is far from the central portion of the film to the marginal portion due to the rotation characteristic. As a result, 0.1 to 1.0 xcexcm in a height difference occurs between the thickness of the central portion spacer and that of the marginal portion spacer.
Thus, a substrate cell-gap of the two sheets is not constantly maintained, so that the luminance at the pixel region is varied with the position of the substrates, thereby generating a spot in a halo form.
Accordingly, the present invention is directed to a method for forming a spacer of a liquid crystal display panel that substantially obviates one or more of problems due to limitations and disadvantages of the related art.
Another object of the present invention is to provide a method for forming a spacer of a liquid crystal display panel that simplifies the process of forming a spacer with a constant thickness and shape.
Additional features and advantages of the invention will be set forth in the description which follows and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a method for forming a spacer of a liquid crystal display panel includes aligning a transcription film on a substrate, selectively performing a thermal imaging on the transcription film to define a spacer forming region, and removing a portion of the transcription film where the thermal imaging is not performed, thereby forming a plurality of spacers on the substrate.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.